Theme's Current Date Doesn't Match WP's

I’m working on a blog that has a theme (Studio Press’ Lifestyle Theme) that is displaying the wrong date in the header. Meanwhile, in the WordPress Admin area under Settings, the date is correct.

When I first noticed the issue, I realized that my computer’s date was wrong as well. I’ve corrected the computer’s date, but the theme is still showing the wrong date.

This hasn’t been an issue until tonight when I was editing the blog using my new computer which had the wrong date. I’m using WordPress 3.0.1.

Also, another blog that I’m hosting in the same location is displaying the right date in its header. Can anyone help?

Thanks!